Zajímavé nálezy lišejníků v údolí Kocáby u Nového Knína (Střední Čechy)

This contribution gives a list of rare, noteworthy and overlooked lichens recorded in the Kocába brook valley near Nový Knín (Middle Vltava Region, Central Bohemia) during several excursions in 2009. This area is strongly influenced by long-term land use: agriculture, forestry, gold mining etc. The lichen flora (especially epiphytic flora) is poorly developed. The ubiquitous acidophilous species distinctly predominate. It is caused by the absence of suitable substrates, former and present air pollution, and the long-term land use. Flavoparmelia caperata, Loxospora elatina, and Pycnora sorophora represent the more precious epiphytic lichens. The shady outcrops of siliceous rocks with Cystocoleus ebeneus, Lecanactis latebrarum, Opegrapha gyrocarpa, and Enterographa zonata occur quite often in the Kocába brook valley. In the study area the valuable lichen communities grow on iron-rich substrates. Acarospora sinopica, Lecanora epanora, and Rhizocarpon furfurosum are characteristic of these communities. Lecanora compallens and Rhizocarpon furfurosum are both reported for the second time from the Czech Republic.